95 cougar temp problem can any one help

ok here is the deal my car is running fine. The temp gauge is showing that the car is running hot, but the cooling fan does not come on until the temp gauge nearly redlines but is still well above set point when it turns off. I know what your thinking heat sensor or gauge right. HMMM i dont know. I replaced the the heat sensor or sending unit what ever its called, and started the car I let it idle for 30 min. As the gauge got just past the mid point the fan would kick on and as it fell to mid point it shut off. I then drove it down the road it never went past the mid point. I was quite proud of my self for fixing it. I took it home turned it off. An hour later I started to leave and go pick up my gf from work I make it a mile or two and the thing redlines with me again. Is my car really running hot. It has a new thermastat it has a new heat sensor, it does have a little white smoke and water driping at start up but that goes away. So can anyone solve the mystery. Please help.

 

Have you flow checked your radiator?

With the car cold and radiator cap off do you obseve bubbles in the radiator coolant?

have you tried removing the thermostate temporarily to see what happens?

Have you checked the spark plugs to see if they indicate a problem?

You might buy a infared heat sensor gun to check for hot spots.

You might hook up a light indicator to the fan motor circuit and remote it inside your car so that you can assertain if and when the fan motor comes on while driving.


Have you cjecked the exhaust system for proper pressure flow?

good luck!

 

Have you flow checked and pressure tested your radiator/system to include water pump flow? at higher rpms the pump propellers could be defective (stamped style pumps )or if the tube passages are clogged or head gaskets are failing the problem might only trigger at higher engine rpms.

With the car cold and radiator cap off do you observe bubbles in the radiator coolant?

have you tried removing the thermostat temporarily to see what happens?

Have you checked the spark plugs to see if they indicate a problem (deposits/color/status?

You might buy a infared heat sensor gun to check for hot spots.

Maybe drain the oil when car is cold and or hot to check for water in oil.





You might hook up a light indicator to the fan motor circuit and remote it inside your car so that you can assertain if and when the fan motor comes on while driving.


Have you checked the exhaust system for proper pressure flow?

what about timing ?

good luck!

 

You mentioned timing. The car has just recently become hard to start. It has to spin for a few seconds before it will start. Could that affect the temp?

 

If the timing advances too much it makes the engine run hotter. Some symptoms are mild to moderate backfiring especially when letting off of the gas,pinging engine upon accelleration,hard starting,loss of power,shifting problems